1. Field of the Invention
The invention is related to air bag deployment doors and, in particular, to an air bag deployment door molded with the molding of an instrument panel retainer and which includes an integral tear initiator.
2. Background Art
Air bag restraint systems are currently being required on all passenger automotive vehicles. These air bag restraint systems are conventionally disposed behind the instrument panel or embedded in the steering wheel. For aesthetic purposes, these air bag systems are disposed behind a cover or protective door which in turn are covered by a foam layer and a decorative cover layer. For rapid deployment of the air bag when activated, it is necessary to tear away the decorative layer and the protective cover. The prior art teaches a wide variety of mechanisms to pierce the decorative layer and provide for the rapid removal of the protective door. In some of these mechanisms, such as taught by Bauer, et al, in U.S. Pat. No. 5,48,106 a separate first inflator is used to activate a mechanism to pierce the decorative or external layer of the instrument panel and a second inflation to inflate the air bag. Other mechanisms such as taught by Parker et al. in U.S. Pat. No. 5,108,128 discloses a cutter mechanism displaced by the inflating air bag to cut through the foam layer and external layer of the instrument panel. In other patents such as taught by Ohmija in U.S. Pat. No. 6,250,669 the severing of the cover layer by a sharp edge of the door as it is forced open by the inflating air bag is disclosed. Still in other mechanisms as taught by Vavalidis in U.S. Pat. No. 5,772,240 protrusions attached to the cover pierce the external layers.
These mechanisms have been found to work well however there is always room for improvement. The instant invention is directed to improvements which make the deployment of the air bag quicker, is less complex, has the potential to reduce deployment time and the potential to reduce the size of the inflator.